From cppreference.com
template<classT>structis_member_pointer;(since C++11)std::is_member_pointer is a
.
If T is pointer to non-static member object or a pointer to non-static member function, provides the member constant value equal true. For any other type, value is false.
If the program adds specializations for std::is_member_pointer or std::is_member_pointer_v, the behavior is undefined.
Template parameters
T - a type to check Helper variable template
template<classT>constexprboolis_member_pointer_v=is_member_pointer<T>::value;(since C++17)Inherited from
Member constants
value
[static]
true if T is a member pointer type, false otherwise
(public static member constant)Member functions
operator bool
converts the object to bool, returns value
(public member function)operator()
(C++14)
returns value
(public member function)Member types
Type Definition value_typebooltypestd::integral_constant<bool,value>Possible implementation
template<classT>structis_member_pointer_helper:std::false_type{};template<classT,classU>structis_member_pointer_helper<TU::*>:std::true_type{};template<classT>structis_member_pointer:is_member_pointer_helper<typenamestd::remove_cv<T>::type>{};Example
Run this code
#include<cassert>#include<type_traits>static_assert(!std::is_member_pointer_v<int*>);structS{inti{42};intfoo(){return0xF00;}};usingmem_int_ptr_t=intS::*;usingmem_fun_ptr_t=int(S::*)();static_assert(std::is_member_pointer_v<mem_int_ptr_t>);static_assert(std::is_member_pointer_v<mem_fun_ptr_t>);intmain(){Ss;mem_int_ptr_tpm=&S::i;assert(s.i==s.*pm);mem_fun_ptr_tpmf=&S::foo;assert((s.*pmf)()==s.foo());}See also